Heater core hoses

[gary68plyfury]

Hello all,
My 68 Fury III with 383 is Not putting out good/hot air from the heater core and also the temp gauge, for the engine, barely touches the Normal Operating Range in the gauge. I've only seen the gauge ever hit mid-range was in the heat of the summer at red lights. I'm going to put either a new 180 or 190 thermostat in tomorrow to see if that helps it reach normal temp. I know it has a temp gauge but I'm not sure if it works correctly or it's temp. The car was a AC car but it was removed before me.

My question is the routing of the heater core hoses. Right now, the front hose, from the water pump runs to the heater core to the connection to the right.
The connection to left of it runs to the top of the heater core valve. The bottom of the heater core valve run the back connection on the water pump.
Hope this can be seen in my pics.

Is this correct? Does it even matter?
One pic, I've seen on the internet, the front water pump connection goes to the top connection in the heater core valve. Bottom goes the heater core then back to water pump.

Thanks in advanced.

 

[CBODY67]

The correct routing, with arrows for each hose, is in the Chrysler factory service manual. Free download at www.mymopar.com . If you might not find that particular model year of Plymouth in their listings, Chrysler and Dodge vehicles work too. I know that illustration is in the 1966 Chrysler service manual.

The higher output temp from the heater starts before the temp gauge gets to its normal range, from my experience. The heater in our '66 Newport worked great with the stock 180* thermostat.

 

[gary68plyfury]

The correct routing, with arrows for each hose, is in the Chrysler factory service manual. Free download at www.mymopar.com . If you might not find that particular model year of Plymouth in their listings, Chrysler and Dodge vehicles work too. I know that illustration is in the 1966 Chrysler service manual.

The higher output temp from the heater starts before the temp gauge gets to its normal range, from my experience. The heater in our '66 Newport worked great with the stock 180* thermostat.

I actually downloaded the manual just forgot I had it. It does have my car. I have the hoses for the control valve backwards. I fix that tomorrow and install new thermostat and see what happens. I do have a aftermarket 3core radiator
Thanks for taking your time.

 

[gary68plyfury]

I corrected the hoses.
Since my car no longer has AC, can or should I bypass the heater core valve?

I'm having separate issue with the coolant. In the rad it was nice and green. The coolant/water that came out of the heater core and heater control valve was Really a mud brown. I bypassed heater core section by looping the heater core hose, on the water pump, ran the car for 10 seconds. Then drained the rest of the coolant and it was REALLY mud brown. I can't figure out why the coolant from rad was nice and green ( I drained some coolant so it didn't get messy switching the heater core valve hoses), ran the engine for 10 seconds then the coolant was mud brown. It seems like the coolant from rad wasn't flowing into the engine and/or heater core/valve. I don't know what to say but I'll refill the whole coolant system with new coolant and see what happens.

 

[CBODY67]

If the coolant was "mud" brown, rather than "rusty" brown, that might be because somebody added some Dexcool to a non-Dexcool system, as if to top it off and that was all that was available. If it was "rusty" brown, that's another issue.

Maintaining the water control valve can be optimal as it keeps the the hot water out of the heater core when it is not needed. Otherwise, you have a heat source in the passenger compartment in the summer time. Might not be too bad in the coming months, though.

Good luck on getting everything water-flushed out.

CBODY67

 

[gary68plyfury]

If the coolant was "mud" brown, rather than "rusty" brown, that might be because somebody added some Dexcool to a non-Dexcool system, as if to top it off and that was all that was available. If it was "rusty" brown, that's another issue.

Maintaining the water control valve can be optimal as it keeps the the hot water out of the heater core when it is not needed. Otherwise, you have a heat source in the passenger compartment in the summer time. Might not be too bad in the coming months, though.

Good luck on getting everything water-flushed out.

CBODY67

CBODY67, Thank you for taking your time to help.
No Dexcool in it. I put in a new aluminum 3 core in March of 2023.

I'll flush it one day very soon and leave in the heater control valve, then use 50/50 coolant. But doesn't the sliding temp control, inside passenger compartment, keep the hot water out of the heater core?

 

[CBODY67]

At to the "50/50" coolant . . . on the cars when they were new, with their original radiators (in our case, the 26" factory a/c radiators), with the radiator cold water flushed (or at least drained completely), it would take 8-9qts to refill the radiator only. As the block had fresh water in it. That 8-9qts was 1/2 the cooling system capacity. Which made it 50-50 at that point. When I could coax a fully 9qts in, it put the protection down to -34*F, rather than the normal -20*F with 8qts.

SO, if you drain the block and radiator, then put 50-50 coolant in it, that's what you get. IF you leave the water in the block and use the (now called "Concentrate") full-strength coolant in it, you get 50-50 concentration as a result. IF you start with 50-50 in the radiator, with another 9qts of clear water in the block, that 50-50 is going to be diluted MORE, So start with full-strength coolant, not the 50-50 stuff.

This can become more important with an aluminum radiator, which holds less than 8qts of coolant.

As to the water valve, keep it fully functional.

Just some thoughts,
CBODY67

 

[gary68plyfury]

Update. Pulled out the thermostat and it's working fine. My radiator fan is a non-clutch type, so it's always spinning/pulling air. Sat in my driveway, when it was 45F outside, and ran the car for 25 minutes and the thermostat never opened. Engine never reached 180F to open thermostat. Had my had infrared thermometer helping me. I was watching the coolant with cap off the radiator. The hottest the infrared read was about 150 to 160 and that was after shutting off heat to the interior

I finally put cardboard in front of the radiator and revved the engine. Finally the thermostat opened, coolant was flowing and the temp needle in the temp gauge on the dashboard was standing straight up or half was between Cold and Hot. In the year and half I've owned the car, I've never seen the temp gauge reach half way, maybe once or twice. Only happens in traffic at red lights. Give it a mile or half mile and it's running cool again.

So, this coming weekend I'll put cardboard in front of the radiator and drive around and see what happens. If gauge doesn't reach half way ( really it's 180F or normal operating temp), I'll pull the fan off and see what happens. If the engine gets toooo hot, I'll remove the cardboard, drive home and/or put the fan back on. It's winter here and I won't be driving far away.

Sounds like I'll be getting a thermal clutch fan or a electric fan. Or install a 160F thermostat. But now I know why the coolant in the rad was still a nice greenish color and the coolant in the engine and heater core was so rusty brown color, because the thermostat RARELY opened. I'll drain the radiator again and pour in new coolant. I'll probably flush it with once or twice with just water.

 

[MoPar~Man]

In the year and half I've owned the car, I've never seen the temp gauge reach half way, maybe once or twice. Only happens in traffic at red lights. Give it a mile or half mile and it's running cool again.

Out of curiosity, what oil is in the engine?

I bet a lot of people would like to have the problem of a 383 that runs too cold.

 

[gary68plyfury]

Out of curiosity, what oil is in the engine?

I bet a lot of people would like to have the problem of a 383 that runs too cold.

I don't remember exactly but it's 10W-30. I'm thinking Quaker State 10W-30. I changed it this past June. I'll have to check it tonight